South Korea, U.S. form 'integrated' extended deterrence system on sidelines of NATO summit

President Yoon Suk Yeol and U.S. President Joe Biden on Thursday reaffirmed the Washington Declaration, which strengthened the South Korea-U.S. alliance to a nuclear-based partnership last year, and announced a statement on a set of new guidelines.

President Yoon Suk Yeol, right, and U.S. President Joe Biden shake hands during a meeting on the sidelines of the North Atlantic Treaty Organization (NATO) summit on Washington on Thursday. [PRESIDENTIAL OFFICE]

President Yoon Suk Yeol and U.S. President Joe Biden on Thursday reaffirmed the Washington Declaration, which strengthened the South Korea-U.S. alliance to a nuclear-based partnership last year, and announced a statement on a set of guidelines jointly adopted by the Defense Ministry and the Pentagon aimed at strongly responding to North Korea's nuclear provocations.

The two leaders met on the sidelines of the North Atlantic Treaty Organization (NATO) summit in Washington.

The "Guidelines for Nuclear Deterrence and Nuclear Operations on the Korean Peninsula" adopted by South Korea's Defense Ministry and the U.S. Defense Department confirmed that "any nuclear attack by the DPRK against the ROK will be met with a swift, overwhelming and decisive response," referring to the North and South Koreas by their official names, the Democratic People's Republic of Korea and the Republic of Korea.

"All categories of South Korean capabilities will greatly contribute to the joint defense posture of the South-U.S. alliance," said Yoon. "An integrated extended deterrence system has been established between Seoul and Washington."

"The United States' extended deterrence commitment to South Korea is supported by the full range of U.S. capabilities, including nuclear," said Biden.

"The progress made since the establishment of the U.S.-ROK Nuclear Consultative Group (NCG) demonstrates the truly global, comprehensive, strategic alliance between the two countries, the ever-stronger mutual defense relationship, and our shared interest in peace, stability and the complete denuclearization of the Korean Peninsula," the two leaders said in the joint statement announcing the newly adopted guidelines.

"The NCG was established as an enduring bilateral consultative body that has implemented the U.S.-ROK Washington Declaration, directly strengthened U.S.-ROK cooperation on extended deterrence, and managed the threat to the nonproliferation regime posed by the DPRK," the statement continued. "The NCG has facilitated joint U.S.-ROK nuclear and strategic planning with a focus on ensuring the continued safety and security of the people of the ROK, as well as the U.S. service members deployed to the Korean Peninsula, in the face of the advancing nuclear threat posed by the DPRK."

Yoon and Biden further discussed "security protocols and expansion of information sharing; nuclear consultation processes in crises and contingencies; nuclear and strategic planning; ROK conventional support to U.S. nuclear operations in a contingency through conventional-nuclear integration; strategic communications; exercises, simulations, training, and investment activities; and risk reduction practices," according to the statement.

"The main task of the South Korea-U.S. NCG has been to prepare a document providing principles and guidelines for the alliance's nuclear deterrence policy and nuclear closure," said Kim Tae-hyo, first deputy director of the National Security Office, during a briefing in Washington on Thursday after the two leader's meeting. "Today, the two countries' defense ministries made an official signature, and the leaders of South Korea and the U.S. approved it through a joint statement, completing the nuclear deterrence and operation guidelines."

The presidential office said an integrated extended deterrence system between South Korea and the United States has been established. An integrated system means that U.S. nuclear power and South Korea's cutting-edge conventional power are integrated to surpass and respond to North Korean nuclear provocations simultaneously.

"Whereas traditional extended deterrence was determined and provided by the United States, it now means that our organization, people and assets in nuclear operations on the Korean Peninsula have evolved into extended deterrence with the United States," Kim said. "And the United States has confirmed that it will allocate the nuclear assets needed to deter and respond to North Korea to the Korean Peninsula mission in wartime and peacetime."

This means not only responding to an actual nuclear attack but also trying to understand North Korea's movements to determine if it intends to attack.

This would require the activation of U.S. nuclear forces, including nuclear submarines, intercontinental ballistic missiles (ICBMs), and strategic bombers.

"This is the first time that U.S. nuclear assets will be assigned to missions to deter and respond to North Korea," Kim said. "It's a clear upgrade from a conventional forces-based alliance to a nuclear-based alliance."

Meanwhile, NATO's Indo-Pacific Four Partners (IP4), which includes South Korea, Japan, Australia and New Zealand, issued a separate joint statement on Thursday condemning the heightened military cooperation between North Korea and Russia.

"We express grave concern over the increasing military and economic cooperation commitment between the Russian Federation and the DPRK, as highlighted by the signing of the treaty on comprehensive strategic partnership, which is contrary to multiple UN Security Council resolutions," read the statement. "We urge the Russian Federation and the DPRK to abide by the relevant UN Security Council resolutions and immediately cease all such activities that violate these resolutions."

Yoon returned to Seoul late Friday after wrapping up a five-day trip to the United States.

Update, July 13:Added Yoon's return to Korea.

BY LIM JEONG-WON [lim.jeongwon@joongang.co.kr]